If you are driving a car and match your speed to the vehicle in front, it will appear to slow down, relative to you. Albert Einstein said the same isn’t true of the photons emerging from your car headlights, however – they will always travel at light-speed.
This central tenet of Einstein’s theory of special relativity – that the speed of light does not change because of the speed of the observer – has now been proved right more precisely than ever before.
Vahe Gurzadyan and Amur Margaryan at Yerevan State University …
–Credit: New Scientist – Home